user created sounds... recognized by ... umm... say... combo of filetitle & length (should be good enough). If file doesn't exist on receiving pc, data is fired across first (if new auto-rx soundfiles option is turned on).
Its not quite what you're after, you can set commands such as HelloThere to play a sound.
It doesnt send files over the internet, that is a big security risk, instead both contacts have to install the plugin and the sound files you want to play.
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